Mayuko Inoue is a high school girl and one of the closest friends of both Ushio Aotsuki and Asako Nakamura. Her personality is gentle, sweet, and distinctly more feminine compared to her more outspoken friends, yet beneath her calm demeanor lies a quiet but unwavering courage. She harbors a deep, affectionate care for Ushio, though she is fully aware that his heart belongs to Asako and selflessly supports their relationship rather than acting on her own feelings. Over the course of the story, Mayuko develops a unique and tender bond with the yokai Tora. Initially, she treats him almost like a large, grumpy pet, regularly buying him hamburgers as a sign of kindness. As time passes, her feelings deepen into genuine romantic love, and Tora in turn becomes protective of her, saving her life on multiple occasions. Mayuko’s background expands significantly when it is revealed that she is a descendant of a long lineage of powerful female shamans. This heritage grants her the ability to create psychic barriers strong enough to restrain even the immense force of Hakumen no Mono. She later takes in the orphaned boy Kirio Inasa as her stepbrother, providing him with a stable home. Throughout the series, Mayuko evolves from a seemingly ordinary classmate into a crucial spiritual guardian, using her inherited powers to help defend the human world from supernatural threats while remaining an emotional anchor for her friends.